lmkd: Support process types when registering a process

Add an optional process type field into lmkd registration protocol so that
applications can be distinguished from services.

Bug: 129011369
Test: boot and verify native service registration
Change-Id: Ie610b5d07cbe247a55ab31bc079ee5c5923bea11
Signed-off-by: Suren Baghdasaryan <surenb@google.com>